Krakatau

The eruption of Mount Krakatoa in 1883 was one of the most violent volcanic events on record. A huge explosion (150 megatons of TNT) occurred as seawater hit hot magma and turned instantly to steam. The blast was heard over 4,000 km away in Australia and India. The Volcano Explosivity Index (VEI) of the eruption is 6 (colossal).
The whole volcano was destroyed because of the massive explosion. Parts of the volcano fell into the sea and caused giant tsunami (40 meters). The dust from the eruption reached the stratosphere and affected weather worldwide for several years. More than 35,000 people are killed by tsunami and eruption. Only about a third of the pre-1883 island survived the blast.
From 1927 to 1930, there were several underwater eruptions on the site of the old Krakatoa volcano. On August 11, 1930, a new volcano and island appeared. This new volcano and island are called "Anak Krakatau" (Child of Krakatoa).
The island of Anak Krakatoa is a national park. To land on the island, tourist must obtain a permit from Balai Konservasi Sumber Daya Alam (BKSDA).

Most of the tour operators in Labuan and Anyer have a camp during the night at Rakata Island. You can enjoy the eruption of Krakatoa at night from here. If you want to stay in Sabesi island, you can stay at a simple hotel which belongs to the Indonesia Tourism Board, just walking distance from Sabesi island jetty. The contact person is Pak Hayun, mobile +628187013757. The price is reasonable between $20- $30 room which can accommodate 10 people in one room. The private room is little bit more expensive with TV inside but the size is smaller. The private room can only accommodate 4 people. Some people in this island also provide homestay for the travelers. The price is negotiable. If you are adventurous enough, you can try this option.